DCENET Data Collection Program
The DCENET program is used to capture factory data over an Ethernet LAN from network data collection devices. It is specifically designed to work in conjunction with the ET210
series of Ethernet data collection products manufactured by Computerwise, Inc.
The DCENET program establishes a TCP/IP connection with one or more data collection devices on the network. It presents each terminal with a logical series of prompts, captures operator responses, validates them and stores them as records in an ASCII data file. The captured data records can then be used by another application for processing. Applications include (but are not limited to):
Theory of Operation
- Factory floor data collection
- Time & Attendance
- Access control
- Machine Monitoring
The DCENET program will capture real time data from multiple data collection devices attached to the network. Prompts are presented to the operator in a user defined sequence and operator responses are validated and then stored in a data file. The heart of the data collection functionality is provided by a Configuration File which is read by the program when it is started. It is used to build the application tables and control the flow of the data collection process.
A Terminal Table is used to specify the network terminal devices and their associated IP addresses. The DCENET program can operate in either a Client or Server mode. In Client mode the program will attempt to establish a network connection with each terminal specified in the Terminal Table. In the Server mode the program will wait for the terminal device to request a connection and will accept only an IP address included in the Terminal Table. Once a connection is established the program will send a prompt to the terminal device and wait for an operator response.
The prompt sequence is defined and controlled by a Prompt Table which also defines how the operator response should be processed. Once the terminal operator enters a response it can be validated in several ways. If the response passes all validation tests the next logical prompt is presented to the operator. Valid responses can trigger a special operation such as activation of the bell or a relay. If the response fails any of the specified validation test an error prompt can be presented to the operator.
Valid operator responses can be included as a data field in a captured data record. The response data field associated with each prompt can trigger the beginning of a new data record and/or saving of the data record to the data capture file. Each captured data record can include one or more response data fields and optionally a time and/or date stamp. Captured data records are stored in an ASCII delimited data file defined by the associated prompt.
In addition to capturing operator response data the DCENET program can trigger an alarm event. Each alarm is defined by an entry in the Alarm Table and is set for a specific time of day. Typically, alarms are used to activate the terminal bell or a control relay. Alarms can be used to signal the beginning/ending of a work period or to start/stop a control process.
The default operating mode for the DCENET program is the Client mode. In this mode the application program is responsible for initiating a connection with the data collection terminals. When the data Capture function is started the program will attempt to establish a connection with each device specified in the Terminal Table.
The DCENET program can be configured to operate as a server application. In this mode the client data collection terminal is responsible for initiating a connection with the application program. When data the Capture function is started the program will listen for a connection request and will accept connections for devices specified in the Terminal Table. One advantage of this mode over the default Client mode is the ability to locate the data collection terminals behind a firewall for WAN applications.